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Peter Anvin" , kvm@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, Yosry Ahmed Cc: Jim Mattson Content-Type: text/plain; charset="UTF-8" When KVM_X86_QUIRK_NESTED_SVM_SHARED_PAT is disabled and nested NPT is enabled in vmcb12, copy the (cached and validated) vmcb12 g_pat field to vmcb02's g_pat, giving L2 its own independent guest PAT register. When the quirk is enabled (default), or when NPT is enabled but nested NPT is disabled, copy L1's IA32_PAT MSR to the vmcb02 g_pat field, since L2 shares the IA32_PAT MSR with L1. When NPT is disabled, the g_pat field is ignored by hardware. Fixes: 15038e147247 ("KVM: SVM: obey guest PAT") Signed-off-by: Jim Mattson --- arch/x86/kvm/svm/nested.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c index 515a8545e8e0..58574e803812 100644 --- a/arch/x86/kvm/svm/nested.c +++ b/arch/x86/kvm/svm/nested.c @@ -727,9 +727,6 @@ static void nested_vmcb02_prepare_save(struct vcpu_svm *svm) struct vmcb *vmcb02 = svm->nested.vmcb02.ptr; struct kvm_vcpu *vcpu = &svm->vcpu; - nested_vmcb02_compute_g_pat(svm); - vmcb_mark_dirty(vmcb02, VMCB_NPT); - /* Load the nested guest state */ if (svm->nested.vmcb12_gpa != svm->nested.last_vmcb12_gpa) { new_vmcb12 = true; @@ -760,6 +757,13 @@ static void nested_vmcb02_prepare_save(struct vcpu_svm *svm) vmcb_mark_dirty(vmcb02, VMCB_CET); } + if (l2_has_separate_pat(vcpu)) { + if (unlikely(new_vmcb12 || vmcb12_is_dirty(control, VMCB_NPT))) + vmcb_set_gpat(vmcb02, svm->nested.save.g_pat); + } else if (npt_enabled) { + vmcb_set_gpat(vmcb02, vcpu->arch.pat); + } + kvm_set_rflags(vcpu, save->rflags | X86_EFLAGS_FIXED); svm_set_efer(vcpu, svm->nested.save.efer); -- 2.53.0.1213.gd9a14994de-goog